Is my intended A/C condenser location OK?

[Corman2000]

Hey guys,

Planning to install my A/C unit shortly. I am hoping for confirmation from those with more experience that I should be fine putting the condenser here. It's 1M away from the gas meter vent which is the min required amount according to the gas company. Other thing is the telephone box is above it, but is not used.
Unit is a Ducane 4AC13L24P-ALD

Thanks for any input!

 

[WorthFlorida]

The location is good, looks like the breaker panel is on the same wall so it makes it easier for power. There is no dryer vent near by, you're good to go. FYI, the pad will probably need to be pulled away from the home about 8-10 minimum inches so there is enough clearance between the wall and the condenser unit for air flow and access.

The model number you gave is a 2 ton unit. What size home and one or two stories?

 

[Sponsor]

 

[Corman2000]

Thanks for the reply.

Unit will be in the sun, but I don't think there is any avoiding that here. I was hoping to keep it as close to the house, and as close to the gas meter as possible. The pad is 30x30", and the unit is 24.5"x24.5". I hoping to get away with maybe 10" of clearance from the unit to the house. The manual says "a minimum of 12" on three sides". House is a 1450ft/sq single story. Summers are generally below 90°F at peak.

Thanks!

 

[Fitter30]

Have any male dogs ? If you do might want to mount unit high on the wall so it can't be peed on. Pee eats aluminum.

 

[Corman2000]

Should be fine for dogs.

Thanks!

 

[Martin Boring]

I would keep it at least 12"from the house. I know you said your peak is around 90 degrees but you humidity level plays a big part on the size. Here in the mid west our humidity is high in the dog days of summer a 2 ton unit wouldn't cut it in a 1450 sq ft single story house we would install a 3 ton here. Double check your sizing for your area before installing.

 

[Dana]

I would keep it at least 12"from the house. I know you said your peak is around 90 degrees but you humidity level plays a big part on the size. Here in the mid west our humidity is high in the dog days of summer a 2 ton unit wouldn't cut it in a 1450 sq ft single story house we would install a 3 ton here. Double check your sizing for your area before installing.

In most of north America ( but particularly in low-dew point areas like Vancouver B.C.) a 2 ton would be extreme overkill (with conviction) for a 1450' house. If you're installing 3 tonners in Nebraska it probably cools the place off pretty fast, but has pretty short run times most of the season, leading to lower comfort & efficiency.

An outfit in GA that does a lot of HVAC design work and consulting compiled this graphic plotting the square feet per ton at the 1% design loads of several dozen real Manual-Js they performed. (Most of these homes were in the sticky-hot Gulf Coast states):

A three tonner for a 1450 house (483 square feet per ton) would only be about right for the ABSOLUTE WORST performing house in that graphic. It would be fully 2x oversized for the average house under 2000'.

According to the ACCA's design temp data , in Vancouver B.C. the latent loads are essentially zero or even negative, and the 1% outside design temps are under 80F. If anything the 2 tonner is likely to be 2x oversized for the actual load. Even though it hit's the low 90s some summers, it's dry. Summertime outdoor dewpoints rarely break 55F, and average under 50F.

 

[Corman2000]

Thanks for the input, and thanks for checking the numbers. We already own the 2T unit so will be installing it. And yeah, most of the time when it's hot here it's low humidity. House is older and not well sealed/insulated (yet).

Thanks!

 

[Martin Boring]

Dana
I understand what you are saying about Manual J and have ran them a bunch but in eastern Nebraska if you install a 2 or a 2.5 ton in a 1450 average square foot house you will have folks that are not happy. I have installed a 2 ton in a super insulated house and it worked fine but most houses around here are not that way and when the dog days of summer hit like we are having now you need some extra cooling. Never had a problem with short cycle times. They are still building houses around here with 2/4 walls.

 

[Dana]

Dana
I understand what you are saying about Manual J and have ran them a bunch but in eastern Nebraska if you install a 2 or a 2.5 ton in a 1450 average square foot house you will have folks that are not happy. I have installed a 2 ton in a super insulated house and it worked fine but most houses around here are not that way and when the dog days of summer hit like we are having now you need some extra cooling. Never had a problem with short cycle times. They are still building houses around here with 2/4 walls.

The people who aren't happy when the system isn't 2x or more oversized are typically those who take the strategy of turning the AC off when they leave the house, with the expectation that they can bring the indoor temps down from the high-80s into the 70s in under an hour when they get back.

The other situation often calling for 2x oversizing would be situations where there are uncalculated large parasitic cooling loads from uninsulated ducts above the insulation, poorly sealed ducts, or an unbalanced duct system with large air-handler driven air filtration rates to compensate for.

Most of the population of eastern NE (eg the city of Lincoln, and Douglas County which encompasses Omaha) live in areas with codes operating at IRC 2009 levels. It would still be legal to do a 2x4/R13 wall in those counties if there is also R5 continuous insulating sheathing over the structural sheathing. But the contribution of walls to cooling loads are usually small compared to windows and roof. As long as the ducts and air handler are all inside the pressure and insulation boundary of the house and the ducts are reasonably well balanced, the design loads won't usually be outside the middle of the clusters in that graphic in response #7, in which case an oversize factor of 1.2x from the 1% load is usually adequate, and anything over 1.5x tends to be overkill.